The subject matter relates to a semiconductor design technology, and particularly, to a reference voltage generation circuit for a semiconductor device, which is capable of generating a reference voltage maintaining a stable target voltage level even when a bias voltage becomes unstable due to variations of a power supply voltage supplied from outside.
In most electronic circuit systems, generally, a power supply voltage supplied thereto is not constantly maintained, but varies with the passage of time and due to their ambient temperatures, any difference between processes, and generation of heat in electronic systems and semiconductor chips, that is, variations of Process, Voltage, and Temperature (PVT).
These variations cause several unfavorable variations in operating characteristics of semiconductor chips. Thus, it is necessary that circuits in the semiconductor chips can operate regardless of theses variations in most precise semiconductor chips.
One of effective methods that deal with these variations is that a reference voltage generator that supplies a voltage or current to other circuits is provided such that it always generate a constant voltage regardless of the variations.